논문 상세보기
pp.173-182
선망어법의 어회과정에 있어서 어군행동에 관한 기초적인 연구를 목적으로 제주 근해에서 사용하고 있는 고등어 선망어구인 파워불록용 선망(Powetblock seine)과 앞으로 예상되는 단선조작에서의고등어 선망어구인 트리플레스용 선망(Triplex seine)의 두 가지 모형망을 1/180로 제작 하고 선망에 의해 포위된 어군의 망내행동과 양쪽 선단의 개구부를 통하여 도피하는 어군의 행동을 관찰 분석함과 동시에 망단의 개구부의 면적 및 장력변화 등을 해석하였으며, 그 결과는 다음과 같다. 1. 죔줄죄기 소요시간 20분일 때, 개구부로 도피하는 아군의 평균 유영속도는 Powerblcok seine에서 9.71cm/sec, Triplex seine에서 9.97cm/sec였다. 2.죔줄죄기 소요시간 20분중 좀줄을 50% 정도 감아들었을 때, 선망내의 어군은 Powerblock seine의 경우 I section 10%, II section방향으로 10% 유영하는 행동을 보였다. 3.죔줄죄기 소요시간 20분중 10분 경과했을 때, 전면 망단 개구부의 면적 감소율은 Powerblock seine이 63.5%, Triplex seine이 어군도피에 대한 수평적 서단능력이 높았따. 그리고, 좀줄에 걸리는 최대장력은 Powerblock seine이 약 8.1톤, Triplex seine이 8.3톤으로 나타 났는데, 양자의 차이는 그다지 크지 않았다.
This study is a basic research in purse seine fishery : on the behaviour of fish schools of tilapia Tilapia mossambica in the process of catch of the purse seine fishing method. The experiment was carried out for the mackerel purse seine which using of power block by fishing fleet system in the near sea of Cheju Island and as a forecast in the near future on the purse seine fishing, using of triplex net winch by one boat system in the near sea of Norway. These model purse seines were made of the scale of 1/180 of its full scale. The model purse seine test on the escaping behaviour of fish school by gap, area reducing of gap and tension of purse line was carried out in the stagnant water of experimental water tank. Designing and testing for the model purse seines were based on the Tauti's law. The results obtained were as follows : 1. When the time for the completing of pursing was 20 minutes, average swimming speed of fish school through a gap was 9.71cm/sec for powerblock seine and 9.97cm/sec for triplex seine. 2. In the case of pursing time in actual value was 20minutes, at 50 percent of the pursing, swimming behaviour of fish school in purse seine was 10% to I section, 80% to II section, 10% to III sectional direction for powerblock seine and a similar tendency for triplex seine. 3. In the case of pursing time in actual value was 20 minutes, at the time of 10 minutes have proceeded since then, area reducing rate of gap of the seine in projected front view was 63.5% for powerblock seine and 67.5% for triplex seine. 4. In the case of pursing time in actual value was 20 minutes, escaping rate of fish school by gap in projected front view was 70% for powerblock seine and 30% for triplex seine. Maximum tension of purse line was about 8.1 tons for powerblock seine and about 8.3 tons for triplex seine.
